How to Screen Janitors and Custodians: 9 Questions and What to Listen For Screening Interview Template

What kind of buildings have you cleaned, and what did one of your shifts actually look like? Roughly how much square footage were you responsible for, what shift did you work, and were you alone or on a crew?

What this assesses: This is the calibration question, and it sorts candidates faster than anything else on the list. Strong answers name the setting and the scale: a two-floor medical office of about thirty thousand square feet solo on second shift, or a four-person night crew splitting a high school, or day porter coverage in a Class A office tower where the work is constant touch-ups in front of tenants. They know their square footage or at least their route, and they can describe the rhythm of the shift. Pay attention to the difference between day porter work and night crew work, because they are close to opposite jobs. A porter handles people all day and cleans in short bursts. A night custodian handles nobody and has to pace an entire building alone. Someone who has only done one will struggle in the other for reasons that have nothing to do with work ethic. Be cautious with a candidate whose only experience is residential house cleaning applying for a commercial contract, since the equipment, the chemicals, the pace, and the accountability are all different, and be cautious with anyone who cannot describe their area in any concrete terms at all.

What cleaning chemicals did you use, and how did you get them to the right strength? What would you never mix, and what does your employer have to give you before you use a new chemical?

What this assesses: This is the safety question that matters most, because a custodian who guesses at dilution is either wasting your chemical budget, leaving surfaces streaked and sticky, or making something that hurts them. Strong answers describe a dispensing system on the janitor closet wall, or measuring to the label, or using pre-portioned packs, and they treat that as normal rather than as a rule someone imposed on them. They know the classic dangerous combination, chlorine bleach with an ammonia-based glass or all-purpose cleaner, which produces chloramine gas in a small enclosed restroom, and many will also flag bleach with acidic bowl cleaner. On the third part, listen for any recognition of a safety data sheet, training, and PPE, even if they call the SDS a data sheet or just say the binder in the closet. Strong answers also mention labeling a spray bottle after filling it, which is the single most common violation in this trade. Be cautious with more is better, with a candidate who says they eyeball it because they have been doing it for years, and especially with anyone who describes mixing products together to make something stronger. That answer is disqualifying on a site with occupants.

Walk me through exactly how you clean a restroom, in the order you do it. How do you keep from spreading anything from one surface to another?

What this assesses: Restrooms produce most of the complaints in this job, so make the candidate show their process. Strong answers move in an order that makes sense: knock and post a sign, empty trash first, apply bowl cleaner and disinfectant and let them sit while doing something else because dwell time is what actually kills anything, then work top down and dry to wet, finish with the floor, and restock paper and soap before leaving. The cross-contamination half is the real signal. Look for color-coded microfiber cloths or a clear rule that the cloth used on a toilet never touches a sink or a mirror, separate mops or a fresh water change between restrooms and other areas, and gloves changed between tasks. Very strong answers mention touch points by name, meaning the door handle and push plate, the flush valves, the faucet handles, the dispenser buttons, and the stall latches, since those are what people actually touch. Be cautious with an answer that is just spray, wipe, mop, with anyone who describes applying disinfectant and immediately wiping it off, and with a candidate who has no rag rule at all.

What floor equipment have you personally operated, and what is the most involved floor job you have done start to finish? If you have stripped and refinished a floor, walk me through the steps.

What this assesses: This is the pay grade question, so be specific about what your site actually needs before you weight it. Strong answers separate machines they have run from machines they have watched: a walk-behind or ride-on auto scrubber, a low-speed buffer with pads, a high-speed burnisher, a carpet extractor, a wet vac. On a strip and refinish, listen for a sequence with the unglamorous parts included, meaning move the furniture, apply stripper and let it dwell, run the machine with the right aggressive pad, pick up the slurry with a wet vac, rinse and neutralize because finish will not bond over stripper residue, let it dry completely, then lay thin even coats with a clean mop and wait between them. The neutralize step and the number of coats are the tells that someone has actually done it rather than heard about it. Be cautious with a candidate who claims floor tech experience but describes it as mopping and waxing in one pass, and be cautious with someone who lists every machine with no story attached to any of them. A candidate with no hard floor experience is still fine for a lot of routes. Just do not put them on your gym floor and be surprised.

Most of this shift you will be alone in the building with nobody checking on you. Walk me through how you would run an eight-hour shift by yourself. What do you do if you finish your route with an hour left?

What this assesses: This is the single most predictive question for night custodial work and the one candidates think least about. Strong answers describe a route or a sequence they follow so nothing gets skipped, usually working one floor or one wing at a time, and they pace against the clock rather than working fast early and coasting. The extra hour question is the real one. Strong answers go to the list of things that never fit in a normal night, meaning detail work like baseboards, vents, high dusting, glass, chair legs, entry mats, or the projects the supervisor keeps asking about, and some will say they would call or text the supervisor to ask what to knock out. That is a good answer. Be cautious with a candidate who says they would leave early, which tells you the finish line is the clock rather than the building, and be cautious with anyone who cannot describe a route at all, since unsupervised work without a system is how a corner of the building quietly goes uncleaned for a month. Ask a follow-up about how their supervisor knew the work got done, and listen for checklists, sign-off sheets, an app, or inspections, because a candidate used to being measured will accept being measured here.

This job includes building keys and an alarm code, and you will be in offices with laptops, cash drawers, and files on desks. What is your rule for what you touch on someone's desk? What would you do if you found a wallet, or found an exterior door propped open at eleven at night?

What this assesses: You are handing this person the building. Strong answers have a firm and simple rule: they do not move papers, they do not open drawers, they clean around personal items rather than through them, and they never throw anything away that is not in a trash can unless it is tagged. Many good custodians will volunteer the classic trap, which is that a full-looking box or a stack on the floor is not trash unless it is marked, and that they ask first. On the wallet, listen for turning it in to a supervisor or a designated place and documenting it rather than leaving it where it was or putting it somewhere clever. On the propped door, strong answers close and secure it, then report it, and they treat an unexplained propped door at night as something the supervisor or security hears about tonight rather than in the morning. Be cautious with an answer that treats any of this as obvious and moves on without specifics, and be cautious with anyone whose plan for a security issue is to handle it themselves. Also be direct in the same breath about the background check your site requires, because school districts and hospitals have fingerprinting and disclosure requirements that will end a hire in week two if nobody raised them in week one.

Have you ever had to clean up blood, vomit, or another bodily fluid? What did you do, and what training or equipment did you have for it?

What this assesses: Every school, clinic, gym, and public building has this happen, and it is where an untrained custodian gets exposed or leaves a hazard behind. Strong answers describe restricting the area first, putting on gloves and usually eye protection, using an absorbent or a spill kit rather than pushing liquid around with a mop, using a disinfectant rated for the job with real dwell time, bagging waste appropriately, and washing hands afterward. Many will name bloodborne pathogen training directly, and some will mention the hepatitis B vaccine their employer offered, which is a strong signal because that offer is part of what employers with exposure risk owe workers under OSHA's Bloodborne Pathogens standard at [29 CFR 1910.1030](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1030). Be cautious with a candidate who describes mopping it up with the regular mop and bucket, since that spreads it and contaminates equipment used everywhere else, and be cautious with anyone who has never done it and shows visible reluctance, because in a school it will happen in the first month. A candidate with no experience but a willing and careful answer is trainable. A candidate who thinks it is not part of the job is not.

A teacher, nurse, or tenant stops you while you are working and asks you to do something that is not on your list, or complains that an area you cleaned is dirty. What do you say and what do you do?

What this assesses: Custodians are visible, and how they handle being interrupted decides whether your client account stays calm. Strong answers do not get defensive about the complaint. They go look at it, fix it if it takes a few minutes, and tell the supervisor if it points at something bigger like a schedule gap or a failing dispenser. On the off-list request, strong answers use judgment rather than a rule: small and immediate gets handled on the spot, anything that would blow up the route or is somebody else's scope gets a polite yes I will check with my supervisor and an actual follow-through. They never argue about scope in front of the occupant, and they never say that is not my job. Be cautious with a candidate whose instinct is to explain why the complaint is wrong, and be cautious with a candidate who says yes to everything, because that is how a route quietly falls apart and a client learns to route requests around your supervisor. The best answers mention closing the loop, meaning they go back and tell the person what happened.

This position is [shift and days]. How would you get to work, and does that hold up in bad weather or if a shift runs late? The work is on your feet the whole shift with lifting, ladders, and pushing equipment. Any of that a problem? What hourly rate are you looking for?

What this assesses: These are the questions that decide who is still on the crew in month three, and almost nobody asks them until after the offer. Transportation is the top attrition cause in overnight custodial work, because a bus route that works at 6am does not exist at midnight. Strong answers are specific about the car, the ride, or the route and have already thought about the late shift and the winter version of it. On physical demands, strong answers are matter of fact and often ask a clarifying question about the equipment or the ladder height, which is a good sign. On rate, strong answers give a number that lines up with your posted range and, if there is a gap, explain what would close it, usually a shift differential or a floor care premium. Be cautious with a rate well above your band, since that gap does not shrink after training, and be cautious with a vague answer on transportation, which usually means it is not solved. Ask the same questions of every applicant and score the answers against the same [interview scorecard](/glossary/interview-scorecard) rather than reading them one at a time and grading on tone. For running this as a written first round instead of a week of unanswered calls to people who work nights, see [asynchronous screening](/glossary/asynchronous-screening) and [structured interview](/glossary/structured-interview).